I'm guessing this is likely a large part of why the efficacy is so high. From what I gather, parasitic infections are hard to vaccinate against at least in par

I'm guessing this is likely a large part of why the efficacy is so high. From what I gather, parasitic infections are hard to vaccinate against at least in part because at least some of them routinely change their protein markers, so it's hard to identify them. It sounds to me like this counters that.